Theorem necom 2486

Description: Commutation of inequality. (Contributed by NM, 14-May-1999.)

Assertion

Ref	Expression
necom	|- ( A =/= B <-> B =/= A )

Proof of Theorem necom

Step	Hyp	Ref	Expression
1		eqcom 2233	. 2 |- ( A = B <-> B = A )
2	1	necon3bii 2440	1 |- ( A =/= B <-> B =/= A )

Syntax hints:   <-> wb 105   =/= wne 2402

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-5 1495  ax-gen 1497  ax-ext 2213

This theorem depends on definitions:  df-bi 117  df-cleq 2224  df-ne 2403

This theorem is referenced by:  necomi  2487  necomd  2488  difprsn1  3812  difprsn2  3813  diftpsn3  3814  fndmdifcom  5753  fvpr1  5858  fvpr2  5859  fvpr1g  5860  fvtp1g  5862  fvtp2g  5863  fvtp3g  5864  fvtp2  5866  fvtp3  5867  netap  7473  2omotaplemap  7476  zltlen  9558  nn0lt2  9561  qltlen  9874  fzofzim  10427  flqeqceilz  10580  isprm2lem  12689  prm2orodd  12699  tridceq  16663